Dial control system

ABSTRACT

A control system for a conveyor movable in an endless path effects movement of the conveyor in the direction which will result in the shorter travel of a selected article on the conveyor when being brought to a fixed station. A readily calibrated dial for selecting a given article to be transported by the conveyor, and a circuit including a starting switch and a direction-selecting switch operable after such article has been selected as a result of adjustment of the dial, are disclosed.

atent United States 4 1931 Skarbek....................... 200/38Al1/1957 [72] Inventor SteveT. Golden 25B Banner Ave., Venture, Calif.93003 13,454

[21 1 Appl. No.

[22] Filed Feb. 24, 1970 [45] Patented Jan. 11, 1972 [54] DIAL CONTROLSYSTEM 11 Claims, 12 Drawing Figs.

endless path effects movement of the conveyor in the selected article onthe conveyor when being brought to a fixed station. A

readily calibrated dial for selecting a given article to be transportedby the conveyor, and a circuit includin switch and a direction [52][1.8. 198/110, direction which will result in the shorter travel ofa g astarting -selecting switch operable after such article has been selectedas a result of adjustment ofthc dial, are disclosed.

PATENTEDJANI 11272 3.633,- 736 SHEEI 1 OF 6 17 INVENTOR STEVE T. GOLDENPATENTEUJANHBYZ 3 633 73 saw 2 OF 6 INVENTOR. STEVE T. GOLDEN PATENTEDJAN] 1 1972 ShEET 3 [1F 6 INVENTOR STEVE T. GOLDEN PATENIEU JAN] 1 19. 23.633.736

mm u 0F 6 PATENTEDJAHI 1 I972 3,5377, 35

' SHEET 5 [1F 6 INVENTOR. STEVE T. GOLDEN BYWEQMH-J' M DIAL CONTROLSYSTEM BACKGROUND OF THE INVENTION Many forms of conveyors movable in anendless path and carrying articles which are to be retrieved or loaded,at a fixed station convenient to the operator, are used, and in certaininstances, as exemplified by the elevator control system disclosed inLewis U.S. Pat. No. 1,856,876, the conveyor is caused to travel by themore direct path to the fixed station. The present invention employsthis feature of reduced conveyor travel by means of an improved controlsystem, and is particularly well suited for, but by no means limited to,use with conveyors found in establishments where laundry or clothing isbeing processed or stored.

In such establishments any delay, due to the additional time requiredfor a long conveyor to bring a distant article by the longer rather thanthe shorter route to the unloading station, may result in annoyance orinconvenience to a customer as well as unnecessarily wasting theattendants time while waiting for the article to arrive at that station.Thus, if the attendants presence is required to keep the conveyor motoroperating or to stop the same, a loss of his time, which otherwise couldbe employed in other duties, is involved. Moreover, in the use ofautomatic controls for such a conveyor system difficulty frequently isfound in calibrating the conveyor and its control setting and keepingthem in calibrated condition, especially when complex control circuitsare involved. It is these and other difficulties experienced in the useof such conveyors which it is a purpose of this invention to overcome.

SUMMARY OF THE INVENTION The invention comprises a control system for aconveyor having a plurality of article carriers movable in an endlesspath successively past a station and with means for selecting a givencarrier and causing it to be moved to the station by the shorter route,and then stopped automatically thereat. The system includes a manuallyoperable dial assembly which is selectively rotatable in either of twodirections, and with the assembly having a first contact which, uponengaging a second contact, whose position is dependent upon conveyormovement, will interrupt the circuit leading to the motor which drivesthe conveyor. The circuit including these contacts also has a startingswitch which remains inoperative until the first and second contacts areseparated, and also includes a direction-selecting switch governing thedirection of travel of the conveyor and whose position for so governingthe travel direction is established by prior movement of the dialassembly.

Among the objects of the invention re the provision of a control systemfor a conveyor requiring the minimum amount of an attendants time foreffecting operation and stopping of the conveyor; the provision of animproved dial control system for a conveyor serving to move the conveyorin the direction which will bring a selected article carried by thatconveyor to a fixed station by the shorter route, and to stopautomatically at that station; the provision of a conveyor controlsystem which may be easily calibrated or recalibrated in order toprovide for the stopping of any predetermined portion of the conveyor ata preselected station along the path of the conveyor; the provision of acompact dial control assembly which may be mounted at a selectedstation, most convenient for an attendant, along a conveyor framework bybeing detachably secured to the framework; the provision of a conveyorcontrol system with a circuit having an electrical transformer whosesecondary is shunted when the conveyor is at rest thereby to avoidinadvertant restarting of the conveyor; and the provision of a conveyorcontrol system having an operator-actuated toggle switch serving to movethe conveyor in a selected direction while a normally operable automaticcontrol system for the conveyor remains inoperative.

These and other objects and advantages of the invention will become moreapparent as the description proceeds and when considered in conjunctionwith the accompanying drawings in which:

FIG. 1 is a perspective view, with parts broken away, of one form ofconveyors, here shown as a garment storage and retrieving conveyor, withwhich the control system may be employed.

FIG. 2 is a front face view, to a larger scale, of the selector dialmounted on its housing.

FIG. 3 is a perspective view showing one arrangement for mounting thedial housing upon a conveyor framework.

FIG. 4 is a partial sectional view taken on line 4-4 of FIG. 2.

FIG. 5 is a partial sectional view taken on line 5-5 of FIG. 2.

FIG. 6 is a perspective view similar to FIG. 3, but taken rearwardly ofthe dial housing.

FIG. 7 is a detail view indicating the mounting of a garment hanger forthe conveyor and in position to actuate the control mechanism.

FIG. 8 is a side elevation view partly in section and illustrating onemodification of the drive for the dial shaft.

FIG. 9 is a sectional view to a smaller scale, taken on line 99 of FIG.8.

FIG. 10 is an exploded perspective view of the interior face of the dialhousing indicating relative positions of switches, shafts, and metalselector plate.

FIG. 11 is a schematic wiring diagram for the electrical components ofthe apparatus; and

FIG. 12 is a schematic diagram of certain mechanical and electricalcomponents of the apparatus.

Referring first to FIG. 1, one appropriate type of conveyor with whichthe invention may be employed is a garment retrieving apparatus as shownby Golden U.S. Pat. No. 3,265,01 1, but, as will be understood, thepresent invention in its broader aspects is suitable for use with manyforms of conveyors which move in an endless path. For purposes ofillustration and not of limitation, therefore, the conveyor may includea framework with a return end generally indicated at l and a drive endgenerally indicated at 2 and with elongated parallel sidetracks 3extending between the respective ends. The sidetracks as well as thereturn and drive ends of the structure preferably comprise a tubularsection 4 having a longitudinal slot 5 (FIG. 7) in one side thereof andextending the entire distance of conveyor travel. Transverse supports 6and 7 attached to the tubular sections are in turn supported at adesired height by upright standards 8 provided with bases 9.

An array of pivotally interconnected links 10, on which article carriersmay be supported, is in turn supported by a plurality of spaced hooks 11attached at their lower ends to the links and terminating at their upperends in generally horizontal portions 12 projecting through the slot 5of the tubular track, as best shown in FIGS. 7 and 8. Intermediate itsends the hook I l is provided with a laterally projecting portion 13,the purpose of which will later appear, and the extreme end of hookportion 12 is threaded and pivotally receives a matting threaded boreformed in the central portion of a roller plate 14. At each end thisplate 14 has threaded bores receiving bearing screws 15, 15A and uponthese screws a pair of rollers 16, 16A are journaled for rotation withinthe tubular track and in contact with the lower interior surface of thetrack, as more fully disclosed in said U.S. Pat. No. 3,265,01 1.

With further reference to FIG. 1, a control assembly generally indicatedat 17 is suitably mounted upon the conveyor structure at a convenientlocation for the attendant of the equipment, this location herein beingcalled the station, and which normally, but not necessarily, is adjacentthe return end 1 of the conveyor. The control assembly includes ahousing having apertured front and rear wall plates 18 and 19respectively as well as side, top and bottom sections serving jointly toenclose certain mechanical and electrical components later to bedescribed. Adjacent the drive end of the conveyor a gear motor 21 isprovided for driving the array of links 10 through a chain 21A connectedto a drive wheel 22 engaging the array of links, such drive being ineither a clockwise or counterclockwise direction as established by theprior setting of the dial control, now to be described.

Considering now FIGS. 2 to 5, a tubular support 25 is affixed normallyto the rear wall 19 of the housing and within this support a shaft 26 isjournaled for rotation in dependence upon the conveyor movement. A sixtooth pinion gear 27 located within the housing is mounted at one end ofshaft 26 and is driven thereby, while to the other end of the shaft 26 asymmetrical noncircular cam 28, for example of hexagonal shape, isrigidly attached. Six equally spaced radial fingers 29 project from thecam into the path of the portions 13 of the suspension hooks, as seen inFIG. 5, with the result that as the conveyor moves in either directionthe shaft 26 and its pinion 27 is rotated 60 in the appropriatedirection each time a finger 29 is pushed by the engaging hook. Toprevent play of the related elements, a detent including a roller 30carried by a lever 31 suitably mounted on a shield member 32 and withthe roller biased into contact with the faces of the cam 28 by means ofa compression spring 33, is provided. The shield 32 serves to protectthe fingers 29 against damage which might result from the attendanthandling garments at the station, and the action of the detent assuresthat the position to which the pinion 27 is rotated will remainsynchronized with the location of the corresponding links of theconveyor.

As best seen in FIG. 5, the tubular support 25 has attached thereto adownwardly facing concave clamp 35 adapted to encompass an upper portionof the tubular track section 4. A companion clamp 36 which may beadjustably secured to the upper clamp 35, as by means of a bolt 37provides for rigidly mounting the described control assembly and itsattached parts to the conveyor structure at any desired location wherethe operator station is most convenient. As will be understood, theclamps 35 and 36 do not diminish the slot nor interfere with themovement of the hook portions 12.

As a significant feature, pinion 27 is meshed with an electricallyconductive, and much larger, spur gear 40 which is journaled forrotation on a fixed electrically conductive rod 41 attached at one endto a boss 42 on the inner face of the housing rear wall 19. This rod isconnected to ground, as will later become evident. The distal end of rod41 provides a mounting for a tubular shaft 43 which is formed ofinsulating material and which is journaled for rotation on the rod 41independent of the rotation of gear 40 on the same rod. Preferably, thepinion gear 27 has six teeth, one tooth for each finger 29, and gear 40is provided with one tooth for each link 10. Accordingly, a 50 linkconveyor has a 6 tooth pinion and a 50 tooth gear; a 100 link conveyorhas a 6 tooth pinion and a 100 tooth gear. Rigidly attached to shaft 43,as by means of setscrews 44, is a shaft 45 projecting through the frontwall 18 of the housing and having an enlarged head 46 at its outer end.

As shown in FIG. 4, a metal plate 50 is rigidly affixed to theinsulating shaft 43 in a plane normal to the shaft axis and isrotationally adjusted upon manual turning of the attached shaft 45. Onits rear surface the plate 50 carries a rigid contact 51 herein calledthe first switch contact. Radially projecting from the confronting faceof spur gear 40 and positioned in the orbital path of contact 51 is aflexible contact 52, herein called the second switch contact and whoseposition at any given time is indexed with respect to the correspondinglinks of the conveyor due to the engagement of the gear 40 with theindexed position of the pinion 27. As will be understood the contacts 51and 52 establish an electrical circuit when in contact with each otherand contact 52 is sufficiently resilient to permit relative movementthereof across the rigid contact 51 in either direction.

As indicated in FIGS. 4 and a switch for determining the direction ofconveyor movement is provided and conveniently may comprise acylindrical lever 53 formed of insulating material and pivotallyattached at one end by means of a pin 54 to a fixed bracket 55 extendinginwardly from the front plate 18 of the control assembly housing. Acarbon or graphite brush 56 having a flexible conductor 57 attachedthereto is mounted within the lever 53 and is pressed at all timesagainst the surface of plate 50 by means of a compression spring 58housed within the cylindrical lever. As a result, rotational movement ofplate 50 in one or the other direction will cause the directionselection switch to pivot and to occupy either a first or a secondcircuit-energizing position, the purpose of which will later becomeapparent. As part of the direction selecting switch assembly asingle-pole, double-throw toggle switch, FIG. 11, is mounted upon thestationary bracket 55 adjacent the lever 53 with its toggle leaf 60arranged to be engaged and moved by that lever when the lever is movedin one direction and to be free from such engagement when that lever ismoved in the other direction. A leaf-type, toggle spring 61 is archedbetween the end of the leaf 60 and the end of a movable contact 62associated with the operator actuated dial selector now to be described.

Passing now to FIGS. 2 and 5, a dial-type selector disc 70 havinguniformly spaced markings in the form of numerals or letters on its faceis adjustably mounted on shaft 45 with a clutch arrangement. Rigidlyattached to the disc is a knob 71 having a recess in its outer face andinto which the head 46 is adapted to fit with a tight frictionalengagement. One feature of the present invention resides in the ease ofcalibration of the equipment and this is accomplished by having theselector dial or disc 70 spaced from the front plate 18 by a distancegreater than the depth of the recess in head 46. A compression spring 72interposed between the plate 18 and disc 70 serves normally to hold theparts in engagement so that turning of knob 71 turns shaft 45 and itsattached plate 50. However, by pushing the knob 71 and turning the disc70 while the head 46 is out of the recess an adjustment in the relativeangular position of the disc 70 and the plate 50 may be effected.

As will be understood, the several markings on disc 70 correspond to theseveral links on the conveyor on which the articles are positioned andin order to retrieve a selected article at the station it is necessaryto select the same by indexing the disc with respect to a standard. Sucha standard may comprise a fixed reference 73 on the face of plate 18 andfor convenience in promptly noting the relative proximity of the nextarticle to be retrieved, a cooperating mark 74 diametrically across thedisc from mark 73 is provided. Thus, as illustrated, in order to causethe more rapid retrieval of an article from link numbered nine theoperator would rotate disc 70 counterclockwise and thus effect anequivalent movement of the conveyor through the circuits later to bedescribed, while if an article from link numbered fourteen is to beretrieved he would rotate disc 70 clockwise.

Referring now to FIGS. 11 and 12, a suitable transformer includes ahigh-voltage primary 81 connected to lines 82, 83 and a low-voltagesecondary 84 having leads 85, 86 extending therefrom and serving thecontrol system. Leads 87, 88 from the primary extend to a conventionalmotor reversing contactor 89 equipped with coil 90 associated withclockwise rotation of drive motor 21 and with coil 91 associated withcounterclockwise rotation of that motor. The motor itself mayconveniently be of the conventional capacitor start, single-phase,alternating current type having a centrifugal starting switch includinga bridging bar 92 cooperating with contacts 93, 94. The motor alsocomprises a running winding 95 for driving the conveyor and a startingwinding 96 and with the capacitor 97 being in the circuit of winding 96.

The control system includes a contactor-controlling circuit having apushbutton start switch 100, a push button stop switch 101, and amanually operable, normally open toggletype switch 102 all mounted onthe front plate 18 of the housing, and readily accessible to theoperator at the station. Associated with the start switch is anautomatic coil 103 which when energized to establish a holding circuitcauses ganged armatures 104, 105 to engage contacts 106, 107respectively. The stop switch 101 normally engages contacts 108, 109 byits bridging bar 110, the contact 108 being connected to ground by alead 111. The toggle switch 102 includes a manually operable arm 112which optionally may be engaged with either contact 113, or 114, or withneither contact, and is intended for use when the transformer secondaryhas been shunted in the manner later to be described.

OPERATION OF THE DlAL CONTROL SYSTEM Assuming that the last articleretrieved was from link number four of the conveyor and with theconveyor at rest, it will be noted that the spur gear 40 now occupies aposition corresponding to the physical presence of that conveyor linknumber four at the station and that the plate 50 occupies a positionwith its contact 51 in engagement with the contact 52 of that spur gear.The holding circuit for coil 103 now being interrupted, the operatorwishing to retrieve the article on link number 9 by the shorter path ofconveyor travel now turns the disc 70 counterclockwise until the numeral9 coincides with the reference 73. In so doing the plate 50 is suitablyrotated to bring its first contact 51 five link spaces away from thesecond contact 52 of the spur gear 40 which is at rest. Simultaneouslythe turning of plate 50 causes the direction selection switch whosecarbon brush 56 in electrical, as well as mechanical, contact therewithto move to a circuit engaging position corresponding to counterclockwisemovement of motor 2]. In so doing, the contact 62 (FIG. 11) is engagedwith contact 120 which through leads 121 and 122 is connected to oneterminal of the counterclockwise coil 91. The other terminal of thiscoil is connected by leads 123 and 124 to lead 85 at one terminal of thetransformer secondary.

Upon pushing of start switch 100, coil 103 is energized through thecontactor-controlling circuit from the transformer winding, leads 86,125 and 126; switch contact 127, switch bar 128, switch contact 129,lead 130, coil 103, lead 131, contact 109 of the closed stop switch bar110 and contact 108 of stop switch 101, and lead 85 to the transformerwinding 84. Energizing of coil 103 causes armature 104 to engage contact106 and armature 105 to engage contact 107. Thus, when armature 97engages contact 106 a holding circuit is established and the operator isfreed for other duties while the conveyor operates since he does notneed to hold the start switch closed. The holding circuit, of course, ismade from the transformer winding 84 through leads 86, 125, armature104, contact 106, lead 132, coil 103, lead 131, and through the closedstop switch back to the transformer winding 84.

When, therefore, the described holding circuit is established, amotor-actuating circuit also is made ready from transformer winding 84through lead 86, armature 105, contact 107, leaf 133, lead contact 62(which had been moved in the selected direction as a result of movementof the disc 70), contact 120, leads 121 and 122, coil 91, and thence, tothe transformer by leads 123, 124 and 85. As coil 91 is energized itcauses the ganged armatures 135, 136 and 137 associated therewith tobridge the respective pairs of contacts 138, 139; 140, 141 and 142, 143.Simultaneously a circuit is established from the transformer primarythrough leads 87, 145, contacts 138, 139, closed by armature 135, lead146, running winding 95, leads 147, 148 and 88 to the transformerprimary 81. At the same time the starting winding of motor 21 istemporarily energized by the circuit through lead 150 connected towinding 95, contacts 93, 94, closed by the centrifugal starting switchbar 92, leads 151, 153, contacts 141, 140, closed by armature 136, lead154, capacitor 97, winding 96, lead 155, contacts 143, 142, closed byarmature 137 and leads 148 and 88 to the transformer primary 81. As willbe understood, as soon as the motor 21 comes to approximately itsrunning speed the bar 92 disengages from the contacts 93, 94 and themotor continues to run at its rated speed driving the conveyor in acounterclockwise direction until the following events occur.

As each of the conveyor links pass by the station, the projection 13 onthe corresponding hook engages a finger 29 and turns the pinion 27through 60. With an appropriate gear ratio between pinion 27 and thespur gear 40 the second contact 52 is moved incrementally nearer thefirst contact 51 each time a link passes the station. Therefore, in theabove example after five such movements of the spur gear, the chosenlink number nine will arrive at the station simultaneously with thecontact 52 engaging contact 51. At this time the secondary 84 of thetransformer is shunted as follows. Since the rod 41 is grounded as by awire 160 connected to any suitable ground and the terminal connection ofcontact 108 also is grounded through lead 111, the grounded circuit isestablished from rod 41, gear 40, second contact 52, first contact 51,disc 50, brush 56, leads 57, 161, 132, contact 106, armature 104, leads125, 86, secondary winding 84, lead 85, lead 111 to ground, as soon asthe conveyor movement brings contact 52 into engagement with contact 51and corresponding to the retrieval of the selected article at thestation When this occurs, the potential in the described holding circuitfor coil 103 drops and that coil becomes deenergized thus shifting thearmatures 104, 105 and opening the control circuit whereupon thedescribed circuit to motor 21 also is opened by the simultaneousdeenergization of the coil 91.

Significantly, this action which represents an important feature of theinvention assures that mere reclosing of the switch 100 while the firstcontact 51 and the second 52 are still in en gagement, will not restartconveyor movement. Rather, the operator must first select the nextarticle to be retrieved and physically move the disc 70 before theconveyor can be automatically moved.

Assuming that the operator therefore selects the article at another link(involving for most rapid retrieval a clockwise movement of the conveyorand its motor 21), and moves the selector disc 70 accordingly toseparate the first contact 51 and the second contact 52, it will beapparent that the secondary of the transformer will no longer begrounded. Closing of switch 100 of course will again energize coil 103as before described, but since the plate 50 has now been rotated in adifferent direction, the direction-selecting switch lever 53 will havethus been rocked to its second circuit-energizing position and with theleaf 62 now in engagement with contact 162 which is connected to a lead163 extending to a terminal on the clockwise coil 90 via lead 170. Acircuit thus is made through the leads 124 and back to the transformersecondary and coil is energized. lts energization causes the gangedarmatures 164, 165, 166 to close respectively upon the contacts 144,167; 149, 168; and 152, 169. During energization of the clockwise coil90, a circuit is made from the transfonner through lead 86, armature105, contact 107, lead 133, leaf 62, contact 162, lead 163, lead 170,coil 90, and leads 124 and 85 to the transformer.

Closing these armatures establishes a running circuit for motor 21 asfollows: from lead 87 of the transformer primary to contact 144,armature 164, contact 167, leads 171 and 146, running winding 95, andleads 147, 148 and 88 to the transformer. The starting winding 96simultaneously is energized from lead 150, contact 93, bridging bar 92,contact 94, lead 151, contact 152, closed armature 166, contact 169,leads 173 and 155, starting winding 96, capacitor 97, leads 154 and 172,contacts 168, 149, closed by armature 165, and lead 88 to thetransformer primary. As will now be evident the starting winding isenergized in a direction opposite to that described above forcounterclockwise rotation of motor 21 and thus the motor is started in areverse or clockwise direction which corresponds to 'the settingestablished earlier by the operator when he moved the selector disc 70.

As before, when the motor 21 comes up to speed the centrifugal startingswitch causes bridging bar 92 to disengage contacts 93, 94 and the motorwill run in its clockwise direction, since its winding will remainenergized until the conveyor is again stopped by engagement of themoving second contact 52 against the stationary first contact 51.

Under some circumstances the conveyor operator may wish to employ acontrol enabling him to move the conveyor in a chosen direction evenwhile coil 103 is deenergized. The arm 112 of the toggle switch 102normally is out of engagement with contacts 113 and 114, but when movedby the operator into engagement with contact 1 13, for example, acircuit causing energization of the counterclockwise coil 91 will bemade as follows even though control coil 103 is deenergized. Thus, a

circuit will be established from the transformer secondary through leads86 and 125, armature 104, contact 180, lead 181, arm 112, contact 113,lead 122, coil 91, leads 123, 124 and 85 back to the transformer.Likewise, when the operator moves arm 112 of the toggle switch 102 intoengagement with contact 1 14 (the control coil 103 being deenergized) acircuit is established from the secondary through leads 86 and 125,armature 104 contact 180, lead 181, arm 112, contact 114, lead 170, theclockwise coil 90, leads 124 and 85 back to the transformer. In eachsituation, the energization of one of the coils 91 or 90 will effect thedrive of motor 21 in its chosen direction, ut not control circuitthrough coil 103 and the leaf 62 of the direction selecting switch isbeing exerted. When the operator, therefore, wishes to bring the motorto a stop he merely moves the switch arm 112 to its normal position outof engagement with either of contacts 1 13 or 1 14.

In addition, and for safety purposes, the stop switch 101 is providedfor cancelling the automatic operation of the conveyor, and when openedby depressing the bridging bar 110 will open the above-described holdingcircuit of the automatic control coil 103.

Having thus described the general operating circuits of a preferred formof dial control system, it will be apparent that certain mechanicalfeatures of the apparatus are important as well. For example, thecontrol assembly may be compactly arranged in the housing which can bereadily mounted on the conveyor framework at the desired location whichis to serve as the operator station. As seen in FIG. 10, the startswitch 100, stop switch 101, toggle switch 102, bracket 55 and coil 103are mounted on the inner surface of the plate 18 of the housing which,of course, is sufficiently large to accommodate the gear drive and therotatable plate 50. In this gear drive, the ratio between the pinion 27and the spur gear 40 is such as to provide for one complete revolutionof gear 40 for one complete circuit of a given link of the conveyoraround the conveyor track. Preferably, the tubular support 25 is mountedin a slot (not shown) in the removable backwall 19 of the housing, sothat when the control assembly is to be employed on a conveyor having alesser, or a greater number of links, that support may be positioned ata lesser or a greater distance from the axis of rod 41. In this way adifferent gear 40 may be employed so as to retain the proper ratio ofrevolutions of the plate 50 and the length of conveyor. Also, theselector disc 70 is readily removable from the shaft 43 so that adifferent selector disc suitable for use with that different conveyorlength may be installed when the gear 40 is changed.

In the event that it is desired to have the control knob 71 at a lowerelevation, a longer housing may be used as seen'in FIGS. 8 and 9. Inthis embodiment spaced auxiliary stub shafts 185 and 186 are mounted onthe rear wall 19 of the housing and the conveyor-driven shaft 26 entersthat rear wall at a higher elevation well above the axis of thestationary rod 41. The spur gear 40 joumaled on rod 41 is in mesh withpinion 27 which in turn forms part of a pulley 187 joumaled on stubshaft 185. A timing belt 188 drives this pulley and is driven by apulley 189 affixed to the conveyor-driven shaft 26. The timing belt alsopasses around a takeup pulley 190 joumaled for rotation on the stubshaft 186. The stub shafts 186 and 185 are each adjustable in slots (notshown) in the wall 19 to permit the required changing of gear 40, ashereinbefore described, and to adjust tension on belt 188. This belt 188is of the conventional type having toothlike elements on its drivingsurface engaging similar elements on the several pulleys and maintainingregister of movement of the rotating parts. As will be obvious, withthis timing belt drive the ratio between the conveyor length and thesingle rotation of gear 40 may, as an alternate, be accomplished byproper choice of the size of pulleys 189 and 187 as well as the choiceof ratio between pinion 27 and spur gear 40.

With the foregoing description in mind the several objects of theinvention will now be apparent. Upon installation of the equipment theoperator knows the number of identified links 1 1 of the conveyor andhas available for use therewith a selector disc 70 with a commensuratenumber of markings thereon and a plate 50 connected to a gearing whichwill cause that plate to make one revolution when a given link of theconveyor travels one complete circuit around the conveyor track.Accordingly, the operator then declutches the selector disc by pressingupon knob 70 and turns the disc 70 until its marking corresponds withthe conveyor link then resting at the operator station. The knob is thenreleased and spring 72 causes the disc 70 to engage with shaft 45. Theoperator then operates the conveyor several times in both its clockwiseand counterclockwise directions to make sure that it will stop each timewith a selected link at the operator station. lf a misalignment, orimproper engagement for example of a finger 29, is detected, such isthen easily corrected by depressing knob 71 and resetting disc 70.

Moreover, the combined electrical circuitry and mechanical componentsare such as to cause the conveyor to move in the most expeditious andshorter route when an article is being retrieved. Furthermore, theshunting of the transformer secondary after the conveyor comes to restprevents further motion of the conveyor until either the toggle switchis operated, or else a new link is selected followed by a closing of thestart switch.

As will be understood, the positioning of shaft 26 by reason of fingers29 being moved by the projections 13 on the travelling hooks 1 l is notthe sole way of driving the shaft and such a drive may be accomplishedby other means without departing from the invention. For example, shaft26 could be moved by a flexible shaft connected to the rotatable drivewheel 22; or a timing belt driven by that wheel could connect that wheeland shaft 26; or a rigid line shaft system could connect the drive wheel22 and shaft 26.

Having thus described and illustrated the preferred embodiments of theinvention, it will be understood that the invention may also be embodiedin other forms within the scope of the appended claims.

lclaim:

1. For use with a conveyor having a plurality of article carriersmovable in an endless path successively past a station and with meansfor selecting a particular one of said carriers and causing it to besubsequently moved to said station by the shorter route and stoppedthereat; a control system comprising an electrical circuit including amotor for driving said conveyor in either of two directions, a manuallyoperable dial selectively rotatable in either of two directions andarranged to remain at rest while said motor is energized, a first switchcontact connected to said dial and adapted to rest in a positioncorresponding to the dial setting, a second switch contact movable independence upon the movement of said conveyor and in correspondence withthe position occupied by one of the carriers of said conveyor, a movabledirection-selecting switch actuated by movement of said dial and adaptedto occupy either a first or a second circuit-energizing position independence upon the movement of said dial in the selected direction, anda starting switch operable to start said motor following the positioningof both of said first switch contact and said direction-selectingswitch, said circuit being deenergized and said motor being stopped whensaid second switch contact is moved by said conveyor into engagementwith said first switch contact.

2. A control system as defined in claim 1 including a normally engagedclutch interposed between said dial and said first switch contact, saidclutch serving to provide for calibration of the conveyor carriers withthe dial settings, said dial being adapted to be moved to a selectedposition without moving said first contact when said clutch isdisengaged and to move with said dial when said clutch is engaged.

3. A control system as defined in claim 2 including a knob on said dialadapted to be pressed axially of said dial against the bias of a springthereby to disengage said clutch.

4. In a control system for a conveyor having a plurality of articlecarriers movable in an endless path, an electrical circuit including atransformer having a primary and a secondary, a

motor for driving said conveyor in either of two directions andconnected to said primary through a reversing contactor, means foractuating said contactor and comprising a contactor-controlling circuitconnected to said secondary and to said contactor and including a firstswitch contact carried by a dial selectively movable in either of twodirections, a second switch contact movable in dependence upon movementof said conveyor and in correspondence to the position occupied by oneof the carriers of said conveyor, a movable directionselecting switchactuated by movement of the dial and adapted to occupy either a first ora second circuit-energizing position in dependence upon the movement ofthe dial in a selected direction, and a starting switch operable tostart said motor following the positioning of both of said first switchcontact and said direction-selecting switch, said contactorcontrollingcircuit being deenergized and said motor being stopped by shunting ofsaid secondary when said second switch contact is moved by said conveyorinto engagement with said first switch contact thereby to preventfurther automatic movement of said conveyor by operation of saidstarting switch prior to separation of said first and said second switchcontacts.

5. A control system as defined in claim 4 including a normally open,manually operable switch in said contactor-controlling circuit andadapted to energize said contactor by removing said shunting of thetransformer secondary independently of operation of said startingswitch, said manually operable switch being selectively movable topositions causing said contactor to establish circuits from said primaryto said motor for driving said motor in either a clockwise orcounterclockwise direction.

6. In combination, a conveyor supported for orbital path movement aroundan endless rail mounted on a framework, said conveyor having an array ofdepending links for carrying articles in spaced relation to each other,a reversible electrical motor for driving said conveyor in either of twodirections, a control system for causing said motor to drive saidconveyor in the shorter direction to bring a selected link to astationary station and to stop thereat, a housing for said systemdetachably mounted on said rail at said station and having a front walland a rear wall, a conveyor-driven shaft projecting from said rear walland carrying means engageable with said conveyor, a second switchcontact rotatably mounted in said housing and driven by saidconveyor-driven shaft and occupying a position corresponding to thelocation of a chosen link in the conveyor orbital path, a dial-selectorshaft projecting from the front wall of said housing and adapted toremain at rest while said motor is energized, a first switch contactdisposed in said housing and occupying a position corresponding to theangular setting of said dial-selector shaft, means for selectivelyrotating said dial-selector shaft for determining the link to be movedto said station, and electrical circuit means in said control system forcausing said motor to operate and to drive said conveyor to bring saidsecond contact into engagement with said first contact and to deenergizesaid motor when said contacts engage each other.

7. Apparatus as defined in claim 6 including a movabledirection-selecting switch in said circuit means adapted to occupyeither a first or a second selected circuit-energizing positiondetermining the direction of rotation of said motor, saiddirection-selecting switch being moved to the selected position byrotation of said dial-selector shaft.

8. Apparatus as defined in claim 6 wherein said means for rotating saiddial-selector shaft includes an exposed dial spaced from said housingand having indicia thereon corresponding to the number of links on saidconveyor, said dial including an operating knob joining said dial tosaid dial-selector shaft.

9. Apparatus as defined in claim 6 wherein said first switch contact iscarried by an electrically conductive plate mounted in insulatedrelation upon said dial-selector shaft and in fixed relation thereto.

10. Apparatus as defined in claim 6 wherein each of said first andsecond switch contacts are flexibly mounted whereby each contact may bemoved in either direction across the other.

11. Apparatus as defined in claim 6 wherein said means for engaging saidconveyor with said conveyor-driven shaft comprises a plurality offingers attached to the shaft and equally spaced angularly from eachother, said fingers projecting into the path of movement of thesuspension hooks of said links thereby to turn the shaft a commensuratedistance as each hook engages each finger.

1. For use with a conveyor having a plurality of article carriersmovable in an endless path successively past a station and with meansfor selecting a particular one of said carriers and causing it to besubsequently moved to said station by the shorter route and stoppedthereat; a control system comprising an electrical circuit including amotor for driving said conveyor in either of two directions, a manuallyoperable dial selectively rotatable in either of two directions andarranged to remain at rest while said motor is energized, a first switchcontact connected to said dial and adapted to rest in a positioncorresponding to the dial setting, a second switch contact movable independence upon the movement of said conveyor and in correspondence withthe position occupied by one of the carriers of said conveyor, a movabledirection-selecting switch actuated by movement of said dial and adaptedto occupy either a first or a second circuit-energizing position independence upon the movement of said dial in the selected direction, anda starting switch operable to start said motor following the positioningof both of said first switch contact and said direction-selectingswitch, said circuit being deenergized and said motor being stopped whensaid second switch contact is moved by said conveyor into engagementwith said first switch contact.
 2. A control system as defined in claim1 including a normally engaged clutch interposed between said dial andsaid first switch contact, said clutch serving to provide forcalibration of the conveyor carriers with the dial settings, said dialbeing adapted to be moved to a selected position without moving saidfirst contact when said clutch is disengaged and to move with said dialwhen said clutch is engaged.
 3. A control system as defined in claim 2including a knob on said dial adapted to be pressed axially of said dialagainst the bias of a spring thereby to disengage said clutch.
 4. In acontrol system for a conveyor having a plurality of article carriersmovable in an endless path, an electrical circuit including atransformer having a primary and a secondary, a motor for driving saidconveyor in either of two directions and connected to said primarythrough a reversing contactor, means for actuating said contactor andcomprising a contactor-controlling circuit connected to said secondaryand to said contactor and including a first switch contact carried by adial selectively movable in either of two directions, a second switchcontact movable in dependence upon movement of said conveyor and incorrespondence to the position occupied by one of the carriers of saidconveyor, a movable direction-selecting switch actuated by movement ofthe dial and adapted to occupy either a first or a secondcircuit-energizing position in dependence upon the movement of the dialin a selected direction, and a starting switch operable to start saidmotor following the positioning of both of said first switch contact andsaid direction-selecting switch, said contactor-controlling circuitbeing deenergized and saiD motor being stopped by shunting of saidsecondary when said second switch contact is moved by said conveyor intoengagement with said first switch contact thereby to prevent furtherautomatic movement of said conveyor by operation of said starting switchprior to separation of said first and said second switch contacts.
 5. Acontrol system as defined in claim 4 including a normally open, manuallyoperable switch in said contactor-controlling circuit and adapted toenergize said contactor by removing said shunting of the transformersecondary independently of operation of said starting switch, saidmanually operable switch being selectively movable to positions causingsaid contactor to establish circuits from said primary to said motor fordriving said motor in either a clockwise or counterclockwise direction.6. In combination, a conveyor supported for orbital path movement aroundan endless rail mounted on a framework, said conveyor having an array ofdepending links for carrying articles in spaced relation to each other,a reversible electrical motor for driving said conveyor in either of twodirections, a control system for causing said motor to drive saidconveyor in the shorter direction to bring a selected link to astationary station and to stop thereat, a housing for said systemdetachably mounted on said rail at said station and having a front walland a rear wall, a conveyor-driven shaft projecting from said rear walland carrying means engageable with said conveyor, a second switchcontact rotatably mounted in said housing and driven by saidconveyor-driven shaft and occupying a position corresponding to thelocation of a chosen link in the conveyor orbital path, a dial-selectorshaft projecting from the front wall of said housing and adapted toremain at rest while said motor is energized, a first switch contactdisposed in said housing and occupying a position corresponding to theangular setting of said dial-selector shaft, means for selectivelyrotating said dial-selector shaft for determining the link to be movedto said station, and electrical circuit means in said control system forcausing said motor to operate and to drive said conveyor to bring saidsecond contact into engagement with said first contact and to deenergizesaid motor when said contacts engage each other.
 7. Apparatus as definedin claim 6 including a movable direction-selecting switch in saidcircuit means adapted to occupy either a first or a second selectedcircuit-energizing position determining the direction of rotation ofsaid motor, said direction-selecting switch being moved to the selectedposition by rotation of said dial-selector shaft.
 8. Apparatus asdefined in claim 6 wherein said means for rotating said dial-selectorshaft includes an exposed dial spaced from said housing and havingindicia thereon corresponding to the number of links on said conveyor,said dial including an operating knob joining said dial to saiddial-selector shaft.
 9. Apparatus as defined in claim 6 wherein saidfirst switch contact is carried by an electrically conductive platemounted in insulated relation upon said dial-selector shaft and in fixedrelation thereto.
 10. Apparatus as defined in claim 6 wherein each ofsaid first and second switch contacts are flexibly mounted whereby eachcontact may be moved in either direction across the other.
 11. Apparatusas defined in claim 6 wherein said means for engaging said conveyor withsaid conveyor-driven shaft comprises a plurality of fingers attached tothe shaft and equally spaced angularly from each other, said fingersprojecting into the path of movement of the suspension hooks of saidlinks thereby to turn the shaft a commensurate distance as each hookengages each finger.